Kerf-forming method and apparatus



Oct. 20, 1936. J, F JOY 2,057,684

KERF FORMING METHOD AND APPARATUS 0ct. 20, 1936. J, JOY 2,057,684

KERF FORMING METHOD AND APPARATUS Filed June 2l, 1934 3 Sheets-Sheet 2 3 @fg/af 1 l f3 fz 12 zz 13 Oct. 20, 1936.

J. F. JoY 2,057,684

KERF FORMING METHOD AND APPARATUS Filed June 2l, 1954 3 Sheets--Sheet 5 27 I Zzvenvn' ('foJYep/Ffay. g4 ,df/lawn r Patented Aooezo, 1936 g Joseph F. Joy, Claremont, N. 11., :tournoi tosuilivan Machinery Company, a corporation ot Massachusetts Application Juno 21, 1934, sonni No. 731,111 27 claims. (c1. 26a-33) This invention relates to improvements in kerfiormlng methods and apparatus, and with respect to the latter, in improvements in mining machine cutter chains and cutter bars, as commonly used '5 for kerf-forming purposes; and more particularly' to the kerf-forming portions of the chain and the wearing parts of the cutter'bar guideway through which the cutter chain is operated.

In a mining machine cutter chain of the conventional form whereby a relatively wide kerf is cut in the coal vein, one of the chief objections arising out of the use of such wide kerf-forming means is that of the iineness of the cuttings due to theremoval by the cutting means of all the coal between the outer walls of the kerf. These nne cuttings are in the form of fine slack coal, which has a relatively low market value as comparedvwith coarser sizes of coal. Another objection to the conventional form of cutter bar is the relatively rapid wear of the guideways through which the cutter chain travels about the margin of the cutter bar.

The primary object of the present invention is to provide an improved kerf forming means 25,for forming a relatively wide kerf, such as is formed by the conventional form of cutter chain, through the forming of two relatively narrow kerfs or slots in parallel relation, whose outer walls shall be spaced by the width of the nished wide kerf, and breaking away, as cutting pro gresses, the portion of the coal intermediate the narrow kerfs or slots. Another object is to provide improved cutting means for forming a relatively wide kerf while at the same time producing a large amount of commercially valuable coal of substantial coarseness in comparison to the cuttings produced by a conventional kerf cutter. Another object is to provide an improved kerf-forming means for cutting narrow slots or kerfs in parallel relation in the coal, and having associated therewith improved breaking means for breaking away the coal intermediate the parallel kerfs or slots. Yet another object is to provide an improved cutter chain having a parallel series of cutting means whereby parallel kerfs o r slots are cut simultaneously in the coal vein. Still another object is to provide an improved cutter chain linkand bit mounting for a mining machine cutter chain. A further object is to provide an improved cutter bit holder particularly designed to use with a cutter chain of the above character. A further object is to provide, in a cutter chain of the above character, improved core breaker means for breaking away the coal between the parallel slots cut by the cutter chain. Another object is to provide an improved cutter chain of the core forming type, with which the improved breaker means is associated, and having improved cutting means and a common chain portion for actuating the cutting means and the core breaker means. Still another object is `to provide an improved cutter chain guiding cutter bar having improved guiding means whereby the wear of the cutter bar is reduced to a minimum while providing substantial bearing surfaces for the chain. A further object is to provide an improved method of forming a relatively wide ker! by the forming oi parallel narrow kerfs and at intervals breaking down the core of material between the parallel kerfs. These and other objects of the invention will, however, hereinafter more fully appear.

In the accompanying drawings there are shown, for purposes of illustration, several forms which the invention may assume in practice.

In these drawings,-

Fig. 1 is a plan view of one illustrative embodiment of the improved cutter chain.

Fig. 2 is a cross sectional view taken substantially on line 2-2 of Fig. 8, with parts broken away.

Fig. 3 is an enlarged detail sectional view of the improved cutter bit mounting.

Fig. 4 is a detail sectional view taken on line 4 4 of Fig. 3.

Fig. 5 is a detail sectional view taken on line 5-5 of Fig. 3 and showing one of the core breaker means.

Fig. 6 is a cross sectional view taken substantially on line 6--6 of Fig. 8.

Fig. 7 is a fragmentary elevational view of one of the chain blocks.

Fig. 8 is a side elevational view of the cutter chain shown in Fig. 1.

Fig. 9 is a view similar to Fig. 8, showing a modied form of core breaker means.

Fig. 10 is a cross sectional view taken substantially on line IU--IU of Fig. 9.

Fig. 11 is a plan view of a portion of the improved cutter chain, showing still another form of core breaker means.

Fig. 12 isia side elevational view'of a further modied form of cutter chain.

Fig. 13 is a plan view of the cutter chain shown in Fig. 12.

Fig. 14 is a cross sectional view taken on line |4-I4 of Fig. 12.

Fig. 15 is a plan view, with parts broken away in section, showing the improved cutter chainan its associated cutter bar.

chain as shown in Fig. i5, are guided about the margin of a plane cutter bar I having formed about its outer edge a chain guiding groove 2 and composed of top and bottom plates 8 and 4 secured. as by rivets, to a central bar member I. The improved wear means associated with the chain guiding groove is in the form of wear strips l, l, herein in the form of angle members. secured, as by rivets 1, to the plates I and 4 of the cutter bar. The longer anges l of these angle members are arranged parallel with the inner faces of the bar plates and form at their inner sides plane bearing surfaces I with which the cutter chain engages. The shorter flanges of the angle members project outwardly about the outer edge of the bar plates and provide outer plane bearing surfaces I0 with which the links of the improved cutter chain engage, as hereinafter described.

Now referring to the illustrative embodiment of the improved cutter chain shown in Figs. 1 to 8, inclusive, it will be noted'that the chain is of the endless type, comprising a series of links connected together and mounted in the cutter bar guideway for orbital movement about the margin of the cutter bar. This improved chain comprises a series of bit blocks IVI pivotally connected by transverse pivot pins I2 to strap links IJ. Each bit block is provided with front and rear ledge or shelf portions I4, I4 providing plane end abutment surfaces I5; and these abutment surfaces on the different bit blocks are engageable with one another in the manner shown, during movement of the cutter chain along the side portions of the cutter bar guideway, but swing relatively apart as the cutter chain moves about the semi-circular end of the cutter bar guideway; these ledges being provided so that the series of bit blocks abuttingly.a

engage one another during movement of the cutter chain along the sides of the cutter bar. Each bit block II is provided with a portion I6 of U-shaped form, the arms I1, I1 of which each have a socket I8 for receiving a cutter bit IS. As illustrated, these arms are spaced equally with respect to a plane parallel with the outer plane surfaces. of the cutter bar, midway between the latter, and the inner surface of this U-shaped portion is provided with plane surfaces 20 engaging the outer surfaces I0 of the angle wear members 6 of the cutter bar, thereby to provide the increased bearing surface `for the cutter chain.

In this instance, the cutter bit is of rectangular cross section and is provided with cutting points 2I, 2i at its ends so that the bit may be reversed in its socket when one point wears out, thereby to present a sharp point. Secured within the bit block and traversing the bit Asocket is a pin 22, with which the inner end of the cutter bit engages, and this pin limits inward movement of the bit and positions the same within the bit socket. A setscrew 23 threaded within the bit block and engageable with thel bit is' utilized to secure the bit rigidly in position within its socket.v The different bit blocks have the bit sockets I8 arranged in different angular pcsitions to enable lacing of the bit points so that a narrow kerf 24, sufilcient to clear the sides of the arms I1, is cut by the bits. The parallel series of cutter bits carried by the arms at the opposite sides of thecutter chain cooperate to form narrow kerfs or slots 24 in parallel relation, thereby to form therebetween, as the cut- The several forms of the improved cutter' terbarisfedinio thecoai,acore 2l. Astbis core is cut by the parallel series of cutters. it is broken away by wedge-shaped core breakers 20 secured at intervals to the inner sides of certain ones of the arms of certain of the bit blocks. These core breakers act as wedges and have sharp 'inclined surfaces 21 for cutting into the sides of and breaking away the core, in themanner shown in Fig. 2. In a preferred form,v

one bit block out of every four is provided with these core breakers 2l, although it will be evident that many more or less may be provided, as desired or as the rate of penetration of the kerf cutters in the coal may make necessary.

In the modified form of construction shown in Fig. 9. the core breakers 2O may be omitted or. if desired, they may be supplemented by means of core breakers Il. These core breakers are in the form of rotary wedge discs having curved inner sides 3|, and of generally elliptical cross section; and each of these rotatable core breakers is journaled on a stub shaft 22 secured to a chain block 33 pivotally connected to adjacent bit blocks. The rotary core breakers may be rotatably mounted intermediate the bit blocks, all on the upper side or all on the lower side, or may be arranged alternately on the upper and lower sides of the chain. As the parallel kerfs or slots are cut out by the cutter chain to form a core, the rotary core breakers 30 engage the side of the core, in the manner shown in Fig. 10, to break the core away as cutting progresses.

In the modified form of construction shown in Fig. 11, the rotary core breakers 30 are mounted on shafts 34 supported within lugs 35 formed integral with the front ledge I4 of the bit block II. In this form of the invention, these rotary core breakers act in a manner identical to that described above in the form of the invention shown in Figs. 9 and 10.

In the further modified form of construction shown in Figs. 12, 13, and 14, it will be noted that the chain link and bit blcck structure is substantially the same 4as that shown in Figs. 1 and 8. 'I'he rotary wedge discs and their lmountings are, however, in this instance, somewhat modified. In this form of the invention, a series of bit blocks 38 are pivotally connected by transverse pivot pins 39 to strap links 40. Each bit block is provided with front and rear ledge or shelf portions 4I, 4I,and the front ledge of each block has secured thereto, as by welding, a transverse shaft 42 having a central portion of square cross section and oppositely projecting threaded portions 43. As shown in Fig. 14, one of the threaded projections has threaded thereon a bearing 'and retaining bushing 44 on which is journaled a rotary wedge disc 45 having a curved inner wedging surface 46. A similar retaining and bearing bushing 41 is threaded on the opposite projection, but the rotary disc in this instance is omitted. These rotary discs alternate on opposite sides of the bit blocks so that one acts with a wedging action in one direction and the next succeeding disc with a wedging action in the opposite direction and respectively on the opposite sides of the core cut by the parallel series of kerf cutters, thereby to break down the core as cutting progresses. disc supporting shaft each have a front plane surface 48 which engages a similar surface on the rear shelf portion of the adjacent bit block, and

ythese abutting surfaces correspond to the end abutting surfaces I5 of the shelf portions- I4, I4

'I'he square portions of theV of the forms of the invention above described. Otherwise, the form of the invention is similar to the other forms'pf the invention, and the parallel kerf cutters and core breakers act onthe coal in a similar manner;

In the various. forms of the invention, when the cutter bar isn-loved edgewise relative to the coal vein, the parallel series of cutters carried by the series of bit blocks cooperate to form narrow slots or kerfs in parallel relation, thereby to form a core between the outer faces of the slots; and as this core is so formed it is broken away in relatively large lumps by the core breakers carried by the cutter chain. Also, in all forms of the invention, the core breakers act to engage and break down the core as cutting progresses. These and other uses and advantages of the improved cutter chain will be clearly apparent` to those skilled in the art.

While in this application there are specically described several forms which the invention may assume in practice, it vwill be understood that these forms are shown for purposes of illustration and that the invention may be further modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a cutter chain, a series of chain blocks pivotally connected together and each having a U-shaped portion the arms of which are spaced apart to provide a core receiving opening, each arm carrying a cutter bit, said bits being arranged on said arms to cut parallel spaced apart kerfs to form a core received in said opening.

2. In a cutter-chain, a series ofpivotally con- Ainected chain elements forming an .endless chain and carrying spaced series of cutting devices for simultaneously cutting out spaced apart narrow parallel slots of substantial depth in the ma,- terial to be mined to form a relatively wide core therebetween.

3. In a cutter chain, a series of pivotally connected chain elements forming an endless chain and carrying spaced series of cutting devices for simultaneously cutting out spaced apart narrow parallel slots of substantial depth in the material to be mined to form a relatively wide core therebetween, and means associated with the cutting means for breaking down relatively large sections of the core between the slots as cutting progresses.

4. In a cutter `chain, a bit block having a U- shaped portion the arms of which are spaced apart to provide a core receiving opening, each arm carrying a cutter, said cutters being arranged on said arms to cut parallel spaced apart keris to form a core received in said opening.

5. In combination, a cutter bar, and a cutter chain guided on the margin of said bar and carrying parallel series of cutters arranged simultaneously to form spaced apart narrow slots of substantial depth in the material to be mined to form a relatively wide core therebetween.

6. In combination, a cutter bar, a cutter chain guided on the margin of said bar and carrying parallel series of cutters operative simultanec-usly to form spaced apart narrow slots of substantial depth in the material to be mined to form a relatively wide core therebetween, and means carried by said cutter chain for breaking away sections of the core between said slots as cutting progresses.

7. In a cutter chain, a series of pivotally connected chain elements each carrying at each of its opposite sides a cutter, said cutters cooperating simultaneously to form spaced apart narrow parallel slots of substantial depth in the material to be mined to form a relatively wide core therebetween.

8. In a cutter chain, a 'bit block having a U- shaped portion the arms of which each carry a cutter, and core breaker means formed cn the inner sides of the arms of the bit block.

9. In a cutter chain, a bit block having a U- shaped portion the arms of which each carry a cutter. and rotary breaker means mounted on said bit block.

10. In combination, a cutter bar having a chain guideway about its edge, angle wear members having iianges to form wearing surfaces cin the inner sides of the chain guideway and about the outer edge of the bar, and a cutter chain guided in said guideway and having cutter supporting elements of U-shape in planes transverse to the path of chain travel, the arms of which elements carry cutters and the bases of the arms engaging the wear member flanges at the outer edge of the bar.

11. A bit block having a U-shaped portion each arm of which carries a cutter, and wedge shaped core breaker means formed on the inner sides of said arms.

12. The method of forming a Wide kerf in coal or other material, including the simultaneous formation of spaced, parallel, elongated narrow kerfs of substantial depth and of substantially the same depth throughout their length to form an elongated relatively wide core of substantially uniform cross section and periodically exerting laterally on the core between said narrow kerfs a wedging action at points along the core length.

13. The method of forming a wide kerf in coal or other material, including the simultaneous formation of spaced, parallel, elongated narrow kerfs of substantial depth and of substantially the same depth throughout their length to form an elongated relatively wide core of substantially uniform cross section and periodically exerting, as the core between said narrow kerfs is substantially severed from the adjacent mass, a wedging action on said core at points along the length of said core.

14. In a core cutting cutter chain, a series of chain blocks pivotally connected together, cutter supports on said chain blocks, and cutters carried by said cutter supports and arranged thereon to cut parallel kerfs spaced apart and of substantial depth, to form a relatively wide core therebetween, said cutter supports being spaced apart laterally on the chain to form an opening therebetween for receiving the core.

15. In a core cutting cutter chain, a series of chain blocks pivotally connected together, cutter supports on said chain blocks, cutters carried by said cutter supports and arranged thereon to cut parallel kerfs spaced apart and of substantial depth, to form a relatively wide core therebetween, said cutter supports being spaced apart laterally on the chain to form an opening therebetween for receiving the core, and means carried by the chain blocks and movable therewith for breaking down portions of the core as cutting progresses.

16. In an endless chain kerf cutting means for mining purposes, series of cutters for simultaneously cutting spaced apart parallel kerfs of substantial depth in the material to be mined to form a relatively wide core therebetween, and

means mounted on and. movable with the kerf cutting means for periodically exerting a breaking down pressure to the core at points along the length oithe latter as cutting progresses.

- 17. In an-endless chain keri cutting means for mining purposes. series of cutters carried by said endlessl chain for simultaneously cutting spaced apart parallel keris of substantial depth in the material to be mined to form a relatively wide 'l0 `core therebetween, and means carried by said endless chain for engaging the sides oi the core to break downsections of the core as. cutting 18. In an endless chain kerl.' cutting means for l mining purposes, a single endless cutting means having parallel series of cutters respectively carried at the opposite sides thereof for simultaneousLv cutting relatively narrow spaced apart parallel keris of substantial depth in the mate- 20 nal to be mined to form a relatively wide core therebetween. n

t 19. In an endless chain kerf cutting means for mining purposes, an endless chain, parallel series of cutters carried respectively at the opposite 25 sides oi said chain for cutting simultaneously spaced apart parallel kerfs or substantial depth in the material to be mined to form a relatively wide core therebetween, and cutter supporting means carried by said chain and by which said :30, series of-cutters are carried, said supporting means being spaced to form an opening therebetween for receiving the core as cutting progresses.

20. In an endless chain kerf cutting means for '35 mining purposes, parallel series oi' cutters carried respectively at the opposite sides of the cutting Vmeans for simultaneously cutting spaced apart parallel kerfs of substantial depth in the material to be mined to forma relatively wide core '40 therebetween, and core breakers carried by the Q50 in the material to be mined to form a relatively wide core therebetween. cutter supporting means carried by said chain and by which said series of cuttersv are carried. said supporting means being spaced to form an opening therebetween for 55 receiving the core as cutting progresses, and core breakerscarried by said chain for breaking down sections of the core as cutting progresses.

22. In a cutter chain, a series of chain blocks pivotaliy connected together and each having a U-shaped cutter support portion, the side arms of said portions being spaced apart to provide a core opening therebetween, and cutters carried by the arms of said portions for cutting parallel keri's to form a core received in the space between said side arms.

23. In a cutter chain, a series of chain blocks pivotally connected together and each having a U-shaped cutter support portion, the side arms of said portions being spaced apart to provide a core' opening therebetween, cutters carried by the arms of said portions for cutting parallel kerfs to form a, core received in the space between said side arms, and means carried by the chain for breaking oi sections oi the core as cutting progresses. l

24. The method of forming a wide kerl.' having a straight inner wall in coal or other materials including the simultaneous formation of straight, spaced apart, parallel narrow kerfs of substantial length and depth and periodically exerting laterally on the material between -said narrow kerfs a wedging action.

25. 'Ihe method of forming a wide kerf having 26. yIn an endless chain kerf cutting means for Y mining purposes, series of cutters for simultaneously cutting spaced-apart parallel kerfs oi substantial depth in the material to be mined to form a relatively wide core therebetween, and wedge-shaped core breaker means mounted on and movable with the kerf cutting means fort periodically exerting a breaking-down pressure on the opposite sides of the core at points along the length oi.' the latter as cutting progresses.

27. In an endless chain kerl cutting means for mining purposes, series of cutters for simultaneously cutting spaced-apart parallel kerfsof substantial depth in the material to be mined to form arelatively wide core therebetween, and core breaking rollers mounted on said endless chain kerf cutting means and movable therewith for periodically exerting a breaking down pressure on the opposite sides of the core at points along the length of the latter as cutting progresses.

JOSEPH F. JOY. 

